Using 64-bit Linux Mint Cinnamon 17.1 with 4.0.4-040004-generic kernel
LibreOffice version: 5.0.0.0.beta1
Build ID: 0a16c3dda4150008d9be6f24cbd15ac198d116d3
Locale: et-EE (et_EE.UTF-8)
Steps to reproduce
* Insert->Frame
* design the frame
* try to rotate - there is no way to do that
Expected result: like with text box there would be the rotate tool available.

There is even in pull-down menu the choice available:
Format->Rotate
...but is greyed out.
The proposal would be to make it work in case of selected panel. There in Format menu are only 90 degree steps and certainly there would be expected also more precise rotation - at least 1 degree step.

The file format uses a <draw:frame> element for the shape, which is generated by the T symbol and for the frame, which is inserted via Insert > Frame, as well. The ODF standard allows a draw:transform attribute on a <draw:frame> element. It is a missing feature in LibreOffice, that transformations are only performed, for what LibreOffice considers to be a shape.
I think it is a hard task, to implement transformations on all kind of <draw:frame> elements. But it would be very useful to have such feature.

I want either the frame to rotate or I want the text box searchable again.
I have a macro that searches the envelope for the word "address", replaces the word with whatever is in the clipboard, then rotates the text box so my xerox printer will print in the right direction (envelopes are pre-stacked in a tray).
This is a Linux problem for me, because Xerox printer libraries are not fully implement for Linux and envelopes is one of the lost pieces. On Linux we had to go back to LibreOffice 5.0 to get the 'search in text boxes' back.
In either case, I agree with the previous comment that this would be a nice feature.

Miklos resolved this issue with his Text Box implementation in LO 4.4.
Steps to reproduce
* Insert->Text Box
* Format -> Text Box -> design the Text Box like your frame
* Format -> Text Box -> Position -> Rotate the Text Box
Frames are a well defined word processing concept with an industry accepted standard. Implementing this request as is would break export to .doc and word perfect formats. Their frame objects do not support rotation. They use Text boxes for this.